Sol-gel synthesized hexagonal boron nitride/titania nanocomposites with enhanced photocatalytic activity.

Graphical abstract Highlights • H-BN/TiO 2 nanocomposites were synthesized by sol-gel method under h-BN sheets solution. • H-BN sheets decreased the charge transfer resistance, inhibiting the charge recombination. • H-BN/TiO 2 formed a new bond B O Ti, and it was a strong interaction between h-BN sheets and TiO 2 nanoparticles. • H-BN/TiO 2 nanocomposites shown excellent photocatalytic performance, and good cycle stability. Abstract Hexagonal boron nitride (H-BN)/titania (TiO 2) nanocomposites photocatalysts were synthesized by a facile sol-gel method. The structure was verified by comprehensive analysis from X-ray diffraction, Raman, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscope and transmission electron microscope. The degradation of organic dyes such as rhodamine B (RhB) and methylene blue (MB) under UV light irradiation was used to measure the photocatalytic activity of the h-BN/TiO 2 nanocomposites. The photocatalytic performance and the stability of H-BN/TiO 2 nanocomposites in the degradation of dyes (MB and RhB) significantly outperformed pure TiO 2 nanoparticles. The formed B O Ti bond in H-BN/TiO 2 gave rise to a strong link between h-BN sheets and TiO 2 nanoparticles, and thus the charge transportation rate was improved and the recombination of electrons and holes was suppressed in the photocatalytic processes. The degradation percentage for RhB and MB reached 98% and 92% within 50 min irradiation. The degradation rate (k) of first-order linear value of h-BN/TiO 2 nanocomposites (0.05952 and 0.0498) for RhB and MB degradation was 3.64 and 4.22 times higher than that of pure TiO 2 (0.01637 and 0.0118). The enhanced photocatalytic property of the nanocomposites was attributed to the reduction in charge recombination and the adsorption interaction between organic dyes and h-BN. Consequently, h-BN sheets hold a great promise to enhance the photocatalytic activity of semiconductive materials. [ABSTRACT FROM AUTHOR]